Justin Gerlach: Partula – Icons of Evolution

Justin Gerlach: Partula – Icons of Evolution

The genus Partula, extremely rich in Polynesian species, will soon get it’s newest monograph (I’m not sure, but it may be the first monograph at all).

The book, written by Justin Gerlach and named “Partula – Icons of Evolution”, is nearly ready to be published, but the project can still be supported.:

https://www.kickstarter.com/projects/507116283/partula-icons-of-evolution

 

Mautodontha consobrina (Garrett)

Huahine Mautodontha Snail (Mautodontha consobrina)

This species, which comes from the island of Huahine, was described in the year 1884.

The shells reach an average size of 0,38 cm in diameter.

Andrew J. Garrett, the species’ author writes in the year 1884.:

Rare and peculiar to one valley.

This statement is all, that is known about this now extinct species, of which obviously only seven museum specimens are in existence.

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References:

[1] Andrew J. Garrett: The terrestrial Mollusca inhabiting the Society Islands”. Journal of the Academy of Natural Sciences of Philadelphia. 2nd series 9: 17-114. 1884
[2] Alan Solem: Endodontoid land snails from Pacific Islands (Mollusca: Pulmonata: Sigmurethra). Part I, Family Endodontidae. Field Museum of Natural History Chicago, Illinois 1976

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mautodontha-consobrina-mc

Depiction from: ‘G. W. Tryon; H. A. Pilsbry; u.a.: Manual of Conchology. Second Series: Pulmonata Vol. 3, Helicidae Vol. 1. 1887’

http://www.biodiversitylibrary.org

Partula fusca Pease

Brown Tree-Snail (Partula fusca)

The Brown Tree-Snail, whose shells were not always brown colored, but were as variable as the shells of most tree-snails, was endemic to the island of Ra’iatea.

The species was obviously not a tree dweller but terrestrial.

The Brown Tree-Snail, like most of its relatives from the island of Ra’iatea, died out at the end of the 20th century.

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partula-fusca-mc

Depiction from: ‘George W. Tryon; Henry A. Pilsbry; u.a.: Manual of Conchology. Second Series: Pulmonata Vol. 20, Caecilioides, Clessula and Partulidae. Index to Vols. 16-20. 1909-1910’

http://www.biodiversitylibrary.org

Partula auriculata Broderip

Ear-shaped Tree-Snail (Partula auriculata)

This species was decsribed in the year 1832.

The Ear-shaped Tree-Snail was an endemic species of the island of Ra’iatea and disappeared shortly after the introduction of the Rosy Wolfsnail (Euglandina rosea (Férussac)) to the island. In the year 1992, when the species was seen for the last time, only a few individuals were left.

The species was not found during field surveys in the years 1994 and 2000, nor during any other subsequent survey, and therefore is considered extinct now.

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partula-auriculata-mc

Depiction from: ‘George W. Tryon; Henry A. Pilsbry; u.a.: Manual of Conchology. Second Series: Pulmonata Vol. 20, Caecilioides, Clessula and Partulidae. Index to Vols. 16-20. 1909-1910’

http://www.biodiversitylibrary.org

Minidonta aroa Brook

Aroa Minidonta Snail (Minidonta aroa)

This species was described in the year 2010 from subfossil shells that were found in the sandy soil of the coastal plains between the villages of Aro’a and Arorangi on the southwest coast of the island of Rarotonga.

The shells reach an average size of 0,25 to 0,3 cm in diameter.

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The species, which obviously was restricted to lowland areas, died out most probably already shortly after the colonization of the island by Polynesians.

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References:

[1] F. J. Brook: Coastal landsnail fauna of Rarotonga, Cook Islands: systematics, diversity, biogeography, faunal history, and environmental influences. Tuhinga 21: 161-252. 2010

Anceyodonta ganhutuensis Cooke & Solem

Gahutu Disc Snail (Anceyodonta ganhutuensis)

The Gahutu Disc Snail was described in the year 1976 based on subfossil shells, which had been found near the Gahutu Bay (not Ganhutu!) on the island of Mangareva, shells of this species were subsequently found on the island of Taravai as well.

The shells of this species reach an average size of 0,17 to 0,22 cm in diameter.

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References:

[1] Alan Solem: Endodontoid land snails from Pacific Islands (Mollusca: Pulmonata: Sigmurethra). Part I, Family Endodontidae. Field Museum of Natural History Chicago, Illinois 1976
[2] Ahmed Abdou; Philippe Bouchet: Nouveaux gastéropodes Endodontidae et Punctidae (Mollusca, Pulmonata) récemment éteints da l’archipel des Gambier (Polynésie). Zoosystema 22(4): 689-707. 2000

Sinployea clista Solem

Closed Sinployea Snail (Sinployea clista)

This species was described in the year 1983.

The ‘species’ occurs on the islands of Tutuila and ‘Upolu, the respective populations, however, differ from each other, and with certainty represent at least distinct subspecies, or possibly even species.

The shells reach sizes of about 0,21 to 0,29 cm in diameter. [1]

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The population of the island of ‘Upolu was not found again during field searches in the years from 1992 to 1994, and is now most probably wiped out. [2]

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References:

[1] Alan Solem: Endodontoid land snails from Pacific Islands (Mollusca: Pulmonata: Sigmurethra). Part II, Families Punctidae and Charopidae, Zoogeography. Field Museum of Natural History Chicago, Illinois 1983
[2] Robert H. Cowie; A. C. Robinson: The decline of native Pacific island faunas: changes in status of the land snails of Samoa through the 20th century. Biological Conservation 110: 55-65. 2003

Taipidon octolamellata (Garrett)

Eight-grooved Taipidion Snail (Taipidon octolamellata)

This species comes from the island of Hiva Oa, it was described in the year 1887, and obviously died out shortly after.

~~~

Obviously, there is only a single voucher specimen left today, a shell with a size of about 0,4 cm in diameter.

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References:

[1] Alan Solem: Endodontoid land snails from Pacific Islands (Mollusca: Pulmonata: Sigmurethra). Part II, Families Punctidae and Charopidae, Zoogeography. Field Museum of Natural History Chicago, Illinois 1983

Minidonta matavera Brook

Matavera Minidonta Snail (Minidonta matavera)

The Matavera Minidonta Snail from the island of Rarotonga was described in the year 2010.

This species is known only from empty shells, some of which are in a subfossil condition, while others appear relatively fresh, suggesting a relatively recent extinction date.

The shells reached a height of about 0,25 cm. [1]

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References:

[1] Fred J. Brook: Coastal landsnail fauna of Rarotonga, Cook Islands: systematics, diversity, biogeography, faunal history, and environmental influences. Tuhinga 21: 161-252. 2010

Anceyodonta gatavaensis Abdou & Bouchet

Gatavake Disc Snail (Anceyodonta gatavakensis)

This species was described in the year 2000.

The Gatavake Disc Snail is known only from subfossil shells, which hed been found near the village of Gatavake at the northwest coast of the island of Mangareva.

The somewhat dome-shaped shells reached an average size of 0,22 cm in diameter. [1]

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References:

[1] Ahmed Abdou; Philippe Bouchet: Nouveaux gastéropodes Endodontidae et Punctidae (Mollusca, Pulmonata) récemment éteints da l’archipel des Gambier (Polynésie). Zoosystema 22(4): 689-707. 2000